Cal-am Water Company - Duarte Water System
MyTapWater.org's tap water quality report is the compilation of data collected from federal, state, and local government agencies, most prominently the EPA. We strive to populate the report with the latest data concerning water contaminants, lead and copper levels, and water quality violations. We only collect drinking water data from public water systems.
PWS Service Information
PWS ID: CA1910186
Type : Community water system
EPA Region : 09
Primary Service Area: Residential Area
Primary Source: Ground water
Population Served: 24,486
Contact Information
HOFER, GARRY HOFER, GARRY 8657 GRAND AVENUE ROSEMEAD, CA 91770 [email protected]
This public water system services 1 municipality in 1 county.
Summary Results
A summary view of tests in which a water contaminant found to exceed the Maximum Contaminant Level ( MCL) set by the EPA.
Maximum Contaminant Levels Exceeded (by year):
Contaminant Detailed Results
This a view of violations of maximum contaminant levels. Use the expanded view see result data for a drinking water contaminant, the minimum level that can be recognized in a test (MRL), and upper limit that is considered healthy (HRL).
Below health limit
Exceeded health limit
Year
Test Date
MRLMinimum Reporting Level
HRLHealth Risk Limit
Test Result
2013
2013-09-10
20
210
200
2013
2013-09-10
20
210
110
2013
2013-09-10
20
210
210
2013
2013-09-10
20
210
< 20
2013
2013-09-10
20
210
< 20
2013
2013-09-10
20
210
< 20
2013
2013-09-10
20
210
< 20
2013
2013-09-10
20
210
< 20
2013
2013-09-10
20
210
< 20
2013
2013-03-13
20
210
93
2013
2013-03-13
20
210
< 20
2013
2013-03-13
20
210
< 20
2013
2013-03-12
20
210
190
2013
2013-03-12
20
210
< 20
2013
2013-03-12
20
210
220
2013
2013-03-06
20
210
< 20
2013
2013-03-06
20
210
< 20
2013
2013-03-06
20
210
< 20
Below health limit
Exceeded health limit
Year
Test Date
MRLMinimum Reporting Level
HRLHealth Risk Limit
Test Result
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
1.02
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-09-10
0.07
0.35
< 0.07
2013
2013-03-13
0.07
0.35
< 0.07
2013
2013-03-13
0.07
0.35
0.4
2013
2013-03-13
0.07
0.35
< 0.07
2013
2013-03-12
0.07
0.35
< 0.07
2013
2013-03-12
0.07
0.35
< 0.07
2013
2013-03-06
0.07
0.35
< 0.07
2013
2013-03-06
0.07
0.35
< 0.07
2013
2013-03-06
0.07
0.35
< 0.07
Other Water Contaminants Tested
The following contaminants were tested and found to be within national EPA guidelines.
Contaminant
MRLMinimum Reporting Level
HRLHealth Risk Limit
Avg Result
chromium-6
0.03
0
0.2689
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.03
0
0.21
2013
2013-09-10
0.03
0
0.2
2013
2013-09-10
0.03
0
0.32
2013
2013-09-10
0.03
0
0.16
2013
2013-09-10
0.03
0
0.11
2013
2013-09-10
0.03
0
0.14
2013
2013-09-10
0.03
0
0.16
2013
2013-09-10
0.03
0
0.22
2013
2013-09-10
0.03
0
0.35
2013
2013-03-13
0.03
0
0.34
2013
2013-03-13
0.03
0
0.19
2013
2013-03-13
0.03
0
0.31
2013
2013-03-12
0.03
0
0.54
2013
2013-03-12
0.03
0
0.46
2013
2013-03-12
0.03
0
0.65
2013
2013-03-06
0.03
0
0.12
2013
2013-03-06
0.03
0
0.17
2013
2013-03-06
0.03
0
0.19
[+] Expand Test Data
cobalt
1
70
< 1
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-09-10
1
70
< 1
2013
2013-03-13
1
70
< 1
2013
2013-03-13
1
70
< 1
2013
2013-03-13
1
70
< 1
2013
2013-03-12
1
70
< 1
2013
2013-03-12
1
70
< 1
2013
2013-03-12
1
70
< 1
2013
2013-03-06
1
70
< 1
2013
2013-03-06
1
70
< 1
2013
2013-03-06
1
70
< 1
[+] Expand Test Data
molybdenum
1
40
1.6944
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
1
40
1.6
2013
2013-09-10
1
40
1.7
2013
2013-09-10
1
40
2.3
2013
2013-09-10
1
40
< 1
2013
2013-09-10
1
40
1.9
2013
2013-09-10
1
40
1.7
2013
2013-09-10
1
40
2.3
2013
2013-09-10
1
40
1.7
2013
2013-09-10
1
40
1.9
2013
2013-03-13
1
40
2.3
2013
2013-03-13
1
40
< 1
2013
2013-03-13
1
40
1.8
2013
2013-03-12
1
40
2
2013
2013-03-12
1
40
2.1
2013
2013-03-12
1
40
1.9
2013
2013-03-06
1
40
1.8
2013
2013-03-06
1
40
2.3
2013
2013-03-06
1
40
1.2
[+] Expand Test Data
strontium
0.3
1500
439.3722
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.3
1500
473.6
2013
2013-09-10
0.3
1500
341.3
2013
2013-09-10
0.3
1500
445.5
2013
2013-09-10
0.3
1500
566.4
2013
2013-09-10
0.3
1500
435.7
2013
2013-09-10
0.3
1500
311.8
2013
2013-09-10
0.3
1500
452.9
2013
2013-09-10
0.3
1500
511.3
2013
2013-09-10
0.3
1500
549.5
2013
2013-03-13
0.3
1500
426.6
2013
2013-03-13
0.3
1500
453.2
2013
2013-03-13
0.3
1500
504.6
2013
2013-03-12
0.3
1500
378
2013
2013-03-12
0.3
1500
309.1
2013
2013-03-12
0.3
1500
306
2013
2013-03-06
0.3
1500
494.2
2013
2013-03-06
0.3
1500
442.3
2013
2013-03-06
0.3
1500
506.7
[+] Expand Test Data
vanadium
0.2
21
1.75
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.2
21
1.9
2013
2013-09-10
0.2
21
1.9
2013
2013-09-10
0.2
21
1.5
2013
2013-09-10
0.2
21
1.8
2013
2013-09-10
0.2
21
1.3
2013
2013-09-10
0.2
21
1.6
2013
2013-09-10
0.2
21
1.4
2013
2013-09-10
0.2
21
2.3
2013
2013-09-10
0.2
21
2.4
2013
2013-03-13
0.2
21
1.6
2013
2013-03-13
0.2
21
1.4
2013
2013-03-13
0.2
21
2.2
2013
2013-03-12
0.2
21
1.8
2013
2013-03-12
0.2
21
2
2013
2013-03-12
0.2
21
1.9
2013
2013-03-06
0.2
21
1.1
2013
2013-03-06
0.2
21
1.4
2013
2013-03-06
0.2
21
2
[+] Expand Test Data
chromium
0.2
100
0.3278
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.2
100
0.3
2013
2013-09-10
0.2
100
0.4
2013
2013-09-10
0.2
100
0.5
2013
2013-09-10
0.2
100
0.2
2013
2013-09-10
0.2
100
0.3
2013
2013-09-10
0.2
100
< 0.2
2013
2013-09-10
0.2
100
0.3
2013
2013-09-10
0.2
100
0.3
2013
2013-09-10
0.2
100
0.5
2013
2013-04-10
0.2
100
1.1
2013
2013-03-13
0.2
100
1
2013
2013-03-13
0.2
100
< 0.2
2013
2013-03-13
0.2
100
< 0.2
2013
2013-03-12
0.2
100
0.3
2013
2013-03-12
0.2
100
0.5
2013
2013-03-06
0.2
100
< 0.2
2013
2013-03-06
0.2
100
< 0.2
2013
2013-03-06
0.2
100
0.2
[+] Expand Test Data
1,1-dichloroethane
0.03
6.14
< 0.03
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-09-10
0.03
6.14
< 0.03
2013
2013-03-13
0.03
6.14
< 0.03
2013
2013-03-13
0.03
6.14
< 0.03
2013
2013-03-13
0.03
6.14
< 0.03
2013
2013-03-12
0.03
6.14
< 0.03
2013
2013-03-12
0.03
6.14
< 0.03
2013
2013-03-06
0.03
6.14
< 0.03
2013
2013-03-06
0.03
6.14
< 0.03
2013
2013-03-06
0.03
6.14
< 0.03
[+] Expand Test Data
1,2,3-trichloropropane
0.03
0.0004
< 0.03
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-09-10
0.03
0.0004
< 0.03
2013
2013-03-13
0.03
0.0004
< 0.03
2013
2013-03-13
0.03
0.0004
< 0.03
2013
2013-03-13
0.03
0.0004
< 0.03
2013
2013-03-12
0.03
0.0004
< 0.03
2013
2013-03-12
0.03
0.0004
< 0.03
2013
2013-03-06
0.03
0.0004
< 0.03
2013
2013-03-06
0.03
0.0004
< 0.03
2013
2013-03-06
0.03
0.0004
< 0.03
[+] Expand Test Data
1,3-butadiene
0.1
0.0103
< 0.1
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-09-10
0.1
0.0103
< 0.1
2013
2013-03-13
0.1
0.0103
< 0.1
2013
2013-03-13
0.1
0.0103
< 0.1
2013
2013-03-13
0.1
0.0103
< 0.1
2013
2013-03-12
0.1
0.0103
< 0.1
2013
2013-03-12
0.1
0.0103
< 0.1
2013
2013-03-06
0.1
0.0103
< 0.1
2013
2013-03-06
0.1
0.0103
< 0.1
2013
2013-03-06
0.1
0.0103
< 0.1
[+] Expand Test Data
bromomethane
0.2
140
< 0.2
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-09-10
0.2
140
< 0.2
2013
2013-03-13
0.2
140
< 0.2
2013
2013-03-13
0.2
140
< 0.2
2013
2013-03-13
0.2
140
< 0.2
2013
2013-03-12
0.2
140
< 0.2
2013
2013-03-12
0.2
140
< 0.2
2013
2013-03-06
0.2
140
< 0.2
2013
2013-03-06
0.2
140
< 0.2
2013
2013-03-06
0.2
140
< 0.2
[+] Expand Test Data
chloromethane
0.2
2.69
< 0.2
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-09-10
0.2
2.69
< 0.2
2013
2013-03-13
0.2
2.69
< 0.2
2013
2013-03-13
0.2
2.69
< 0.2
2013
2013-03-13
0.2
2.69
< 0.2
2013
2013-03-12
0.2
2.69
< 0.2
2013
2013-03-12
0.2
2.69
< 0.2
2013
2013-03-06
0.2
2.69
< 0.2
2013
2013-03-06
0.2
2.69
< 0.2
2013
2013-03-06
0.2
2.69
< 0.2
[+] Expand Test Data
Halon 1011
0.06
90
< 0.06
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-09-10
0.06
90
< 0.06
2013
2013-03-13
0.06
90
< 0.06
2013
2013-03-13
0.06
90
< 0.06
2013
2013-03-13
0.06
90
< 0.06
2013
2013-03-12
0.06
90
< 0.06
2013
2013-03-12
0.06
90
< 0.06
2013
2013-03-06
0.06
90
< 0.06
2013
2013-03-06
0.06
90
< 0.06
2013
2013-03-06
0.06
90
< 0.06
[+] Expand Test Data
HCFC-22
0.08
0
< 0.08
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-09-10
0.08
0
< 0.08
2013
2013-03-13
0.08
0
< 0.08
2013
2013-03-13
0.08
0
< 0.08
2013
2013-03-13
0.08
0
< 0.08
2013
2013-03-12
0.08
0
< 0.08
2013
2013-03-12
0.08
0
< 0.08
2013
2013-03-06
0.08
0
< 0.08
2013
2013-03-06
0.08
0
< 0.08
2013
2013-03-06
0.08
0
< 0.08
[+] Expand Test Data
PFBS
0.09
0
< 0.09
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-09-10
0.09
0
< 0.09
2013
2013-03-13
0.09
0
< 0.09
2013
2013-03-13
0.09
0
< 0.09
2013
2013-03-13
0.09
0
< 0.09
2013
2013-03-12
0.09
0
< 0.09
2013
2013-03-12
0.09
0
< 0.09
2013
2013-03-06
0.09
0
< 0.09
2013
2013-03-06
0.09
0
< 0.09
2013
2013-03-06
0.09
0
< 0.09
[+] Expand Test Data
PFHpA
0.01
0
< 0.01
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-09-10
0.01
0
< 0.01
2013
2013-03-13
0.01
0
< 0.01
2013
2013-03-13
0.01
0
< 0.01
2013
2013-03-13
0.01
0
< 0.01
2013
2013-03-12
0.01
0
< 0.01
2013
2013-03-12
0.01
0
< 0.01
2013
2013-03-06
0.01
0
< 0.01
2013
2013-03-06
0.01
0
< 0.01
2013
2013-03-06
0.01
0
< 0.01
[+] Expand Test Data
PFHxS
0.03
0
< 0.03
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-09-10
0.03
0
< 0.03
2013
2013-03-13
0.03
0
< 0.03
2013
2013-03-13
0.03
0
< 0.03
2013
2013-03-13
0.03
0
< 0.03
2013
2013-03-12
0.03
0
< 0.03
2013
2013-03-12
0.03
0
< 0.03
2013
2013-03-06
0.03
0
< 0.03
2013
2013-03-06
0.03
0
< 0.03
2013
2013-03-06
0.03
0
< 0.03
[+] Expand Test Data
PFNA
0.02
0
< 0.02
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-09-10
0.02
0
< 0.02
2013
2013-03-13
0.02
0
< 0.02
2013
2013-03-13
0.02
0
< 0.02
2013
2013-03-13
0.02
0
< 0.02
2013
2013-03-12
0.02
0
< 0.02
2013
2013-03-12
0.02
0
< 0.02
2013
2013-03-06
0.02
0
< 0.02
2013
2013-03-06
0.02
0
< 0.02
2013
2013-03-06
0.02
0
< 0.02
[+] Expand Test Data
PFOA
0.02
0.07
< 0.02
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-09-10
0.02
0.07
< 0.02
2013
2013-03-13
0.02
0.07
< 0.02
2013
2013-03-13
0.02
0.07
< 0.02
2013
2013-03-13
0.02
0.07
< 0.02
2013
2013-03-12
0.02
0.07
< 0.02
2013
2013-03-12
0.02
0.07
< 0.02
2013
2013-03-06
0.02
0.07
< 0.02
2013
2013-03-06
0.02
0.07
< 0.02
2013
2013-03-06
0.02
0.07
< 0.02
[+] Expand Test Data
PFOS
0.04
0.07
< 0.04
[+] Expand Test Data
Year
Test Date
MRL
HRL
Test Result
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-09-10
0.04
0.07
< 0.04
2013
2013-03-13
0.04
0.07
< 0.04
2013
2013-03-13
0.04
0.07
< 0.04
2013
2013-03-13
0.04
0.07
< 0.04
2013
2013-03-12
0.04
0.07
< 0.04
2013
2013-03-12
0.04
0.07
< 0.04
2013
2013-03-06
0.04
0.07
< 0.04
2013
2013-03-06
0.04
0.07
< 0.04
2013
2013-03-06
0.04
0.07
< 0.04
[+] Expand Test Data
Lead and Copper Data
Lead and copper are recorded separately from other contaminants because of the Lead and Copper Rule. As with all other results, these are the findings at the water supply level. Lead and copper can be — and often are — deposited in drinking water in between the water facility and your tap.
Sample ID
Contaminant
Sampling Start Date
Sampling End Date
Result
CA62618
lead
2016-01-01
2018-12-31
0mg/L
CA49002
lead
2013-01-01
2015-12-31
0.004mg/L
191018612209L
lead
2012-01-01
2012-12-31
0.006mg/L
CA37571
lead
2010-01-01
2012-12-31
0.006mg/L
191018610084LT1
lead
2010-01-01
2010-12-31
0.006mg/L
191018610099L
lead
2010-01-01
2010-12-31
0.005mg/L
191018610160L
lead
2010-01-01
2010-12-31
0.004mg/L
191018610168L
lead
2010-01-01
2010-12-31
0.006mg/L
191018610172L
lead
2010-01-01
2010-12-31
0.003mg/L
191018610198LT4
lead
2010-01-01
2010-12-31
0.006mg/L
191018609213LT4
lead
2009-01-01
2009-12-31
0.006mg/L
CA18078
lead
2007-01-01
2009-12-31
0.006mg/L
Violations
Known violations of the Safe Drinking Water Act as recorded by the EPA.
No violations found for Cal-am Water Company - Duarte.
Local Water Testing
Find a lab in your area so you can get your tap or well water tested. This list contains both governmental and private labs, all of which are EPA-certified for drinking water testing.
Unable to identify any nearby water testing labs near 91770 .
Water Bill Information
Convenient information about your water service.
Unable to identify any billing information about Cal-am Water Company - Duarte (CA1910186).
What My Water Data Means
Water data isn't always easy to interpret, but by following the links on this page you should be able to have most of your questions answered. By clicking the name of a water contaminant or secondary substance you can learn about that specific substance. Ultimately this page should give you some insight towards learning if your water is safe , what water filter you should buy (if any), and how well your local water compares against other sources.
Sources
The origin of MyTapWater.org's water data is explained on our Data Sources page.
Why Is My Water Data Not More Recent?
The recency of the data for your ZIP code depends on the last your water source was tested, by a federal, state, or local agency. More information about the timing can be determined by learning about the dataset in question and seeing how often the EPA (other another governing body) mandated testing.